What the HECK did she lay now?!?!?!

Hello
My White leghorn just laid the tiniest egg yesterday!!
It is barely an inch long and a little less than an inch wide.
Anybody ever seen anything like this of knows how this can happen?
Have had her since last year and has laid normal eggs so far , even though I did find a wind-egg today and wonder if it is hers.
We only have 2 white layers, so 50% chance , I guess.
The feed is Layena with grit and oster shells, plus they free-range all day.
Anybody any clue???

Occasionally, some young hens will lay eggs that have no yolk whatsoever. These eggs, historically called "cock eggs" because some people erroneously believed that they were laid by roosters, are now often jokingly called "wind eggs" or "fart eggs" by people who raise chickens and encounter these unusual eggs with some regularity.